Apparatus for treating hydrocarbon oils



C. W. STRATFORD APPARATUS FOR TREATING HYDROCARBON OILS Dec. 14, 1937.

Filed March 2'7, 1955 INVENTOR. CMZSfrzvfl-on BY flwlf: ATTORNEY.

Patented Dec. 1937 UNITED I STATES PATENT OFFICE ArrAaA'rUs ron-'ram'rma unmo- CARBON. oms

Charles W. Stratford, Kansas City, Mo., asslgnor to StratfordDevelopment Corporation, Kansas City, Mo., a corporation of DelawareApplication March 2'1, 1935, Serial No. 13,219

7 Claims.

My invention relates to apparatus for treating hydrocarbon oils and moreparticularly to a contactor for contacting a hydrocarbon oil with atreating agent, as for example, acid.

15 is of great importance in order to secure the best treating results.By way of clarification and not by way of limitation, the followingexample is given. When treating a pressure distillate containing a largepercentage of sulphur bodies at atmospheric temperature (70 F.) withrelative large quantities of acid (approximately 12 pounds of 98 percentsulphuric acid), 'the'total contact time between the acid and thedistillate must not exceed one second. It has been found that a contacttime in excess offlthis period will result in polymerization losses andfurther losses or distil- .late by dissolution in the concentratedsulphuric acid. The polymerization losses and distillate losses will beso excessive that the treating process duced, the contacting time couldbe lengthened. Still by way of example, in the treatment of lubricatingoil distillates with sulphuric acid, it is 35 usually necessary to heatthese to a temperature of in the neighborhoodof 180 F. in order toreduce their viscosity to such a point that they may be dispersed andhomogenized with .acid. The contact me which is permissible in thetreatment 40 Of lubri ting oil distillates with sulphuric acid may be aslong as 300 seconds. It will readily be understood by those skilled inthe art that the contact time is usually a function ofthe strength 'andquantity of the acid, the particular hydrocarbon oil" belngtreated andthe temperature at which the treating process takes place.

The difflculties encountered in acid treating in refinery operations andthe unsatisfactory-results which are often attained'for a givenhydrocarbon distillateare caused chiefly by the employment of Acontactor is a mechanical mixer, the con- 0 will be uneconomical. Inthe-above example, if

the temperature of the pressure distillate were re-- agent and thehydrocarbon oil being treated obtained, the determination of the propercontact c s time is impossible.

The temperature in treating processes can be readily controlled by heatexchange. The chemi- 5 cal composition of a particular distillate to betreated can be ascertained and is moreor less constant. The strength ofthe acid, if acid is the r.

" treating agent to be employed, can also be governed and maintained ata uniform point. We have then two variables which ,must be controlled inorder to'get proper results. These are uniformity of dispersion ormixing of the treating agent with the distillate to be treated, and thecontact time during which the acid and the disl5 tillate are to remainin intimate contact with each other..

I have given a case of contacting hydrocarbon 'distillates with acid byway of example. It is to be understood that any of the treating agentsknown to the art which are or may be suitable for the treatment ofhydrocarbon oils,-may be employed in my apparatus. For example, sulphurdioxide, either alone or in combination with benzene, chloroform, or thelike, nitro enzene, phe- I101, dichlor ethyl ether, furfural, propane,mixtures of propane with selective solvents such as methyl ethyl ketone,or the like, may be employed. Likewise, solutions of ,metallic salts ormetallic oxides as well as caustic solutions may be intimately mixedwith hydrocarbon oils in my apparatus. Similarly, oils may be blendedand addition agents may be added to oils by means of my apparatus. Forexample, pour point depressants like the condensation product of achlorinated aromatic hydrocarbon and a chlorinated wax may be intimatelymixed with hydrocarbon oils by means of my 'apparatus. Similarly, filmstrength and oiliness characteristic improvers may be blended withhydrocarbon oils in my ap- 40 paratus. For example, chlorinated diphenylmay be mixed with hydrocarbon oils as oiliness improvers.

One object of my invention is to provide a mechanical mixing devicewhereby intimate mixtures of liquids and/or liquids and finely dividedsolids, as for example diatomaceous earth, bnto- 5Q nite; fullers earth,tripoli, and other filter aids, may be intimately mixed and uniformlydispersed through the liquid. x

' Another object of 'my invention is to provide a mechanical mixingdevice in which the time or Jam,

Another object of my invention is to provide a mechanical contactingdevice in which the volume of the apparatus may be varied in order toprovide a. time interval of contacting which is gas with the liquidbeing contacted in my apparatus.

Other and further objects of my invention will appear from the followingdescription.

In general, my invention contemplates the pro vision of a circularimpeller for establishing a zone of high turbulence and providingstationary shearing blades above the impeller and diffuser vanes belowthe impeller. The impeller establishes a rapid flow of liquid in ashort, continuous path. The direction of flow is constantly beingchanged and the velocity of flow is constantly being altered so that,frequent enforced changes in velocity and direction result. The volumeof liquid within the contacting zone is governed by an adjustable means.

In the accompanying drawing, which forms part of the instantspecification and is to be read in conjunction therewith and in whichlike reference numerals are used to indicate like parts in' the variousviews;

Figure 1 is an elevation partly in section, of an apparatus embodyingone mode of carrying out my invention.

Figure 2 is an elevation of .the lower part of the apparatus shown inFigure 1, with part of the exterior casing broken away.

Figure 3 is a sectional view taken on the line 3-3 of Figure 1.

Figure 4 is a. sectional view taken on the line 4-4 of Figure 1.

Figure 5 is a sectional view taken on the line 5-5 of Figure 1.

More particularly referring now to the drawing, a shell is formed withan upper cylindrical portion I and a lower portion 2, which is made inthe form of a truncated cone. The lower pertion 2 is provided with aspaced shell 3 forming a jacket in which is provided a suitable baflie,as for example spiral baflle 4. Suitably supported from shell I is adriving motor 5 which is con-- nected to shaft 6, which is housed in atube 1. The end 8 of shaft 6 is guided by a bushing 9 in the lowerportion of the apparatus. Keyed to shaft 6 in any suitable manner is animpeller I0. It will be observed that, by putting the driving motor atthe top, leakage and diiliculties which would otherwise be encounteredby a bottom stuffing box are avoided. This is especially advantageous ifacid is used as a treating agent.

Within the lower portion 2 of the shell and spaced therefrom, I provideabaflie I I in the form of a truncated cone. The shell 2 and the bailieII form an annular passageway of progressively increasing crosssectional area. Within this passageway I position a plurality of vanesI2 which extend longitudinally. Lying longitudinally along the interiorsurface of baflle II and extending radially, I provide a plurality ofvanes I3. Directly above the impeller I0 I provide a plurality ofshearing blades I4. Directly below the impeller III I provide aplurality of diffuser vanes I5 by which the liquid is straightened intolinear turbulent flow. Further vanes I6 are provided in the annularpassageway formed in the lower portion of my contactor. A lubricatingdevice I! is contact may be readily controlled and adjusted.

provided for lubricating the lower portion 8 of the shaft 6. A pluralityof manifolds I8 having branch pipes I9 communicating with the interiorof shell I are provided as can readily be seen by reference to Figure 1.These manifolds are the outlet manifolds. Each manifold is provided witha plug cock 20 which controls communication of each manifold with aheader 2 I. Positioned within the cylindrical portion I of the shell Iprovide a float 22 which is made up of a plurality of segments securedto each other by flanges 23 in any suitable manner. In its lowestposition, with my apparatus empty, the float rests upon stops 24. Thefloat may be made of steel or any other suitable material. A wire cable25 passes through stuffing box 26 over pulleys 21 and is secured to anindicator device 28 which is adapted to ride in a .guideway 29 securedto the exterior of the shell I. It will be obvious that, as the float 22rises, the indicator button 28 will drop indicating the position of thefloat within the shell. The liquids to be mixed are charged to thecontactor through inlet nozzle 30, an inlet pipe 3| being providedinteriorly to conduct the liquids to be mixed to a point near the axisof my apparatus.

, By introducing the liquids to be mixed or contacted in this mannerinto the suction of the impeller, there is no danger of having materialswhich are not thoroughly mixed overflowing through the outlet manifold.It will be noted that the outlet manifolds are positioned to skim themixture from the very outside of the shell at points where the mixtureis intimate and homogeneous. A number of eduction points are providedaround the shell to avoid the withdrawal of a mixture from entirely onepoint, thus avoiding the short circuiting of unmixed liquids. The plugcocks 20, 20a, 20b, and 200 determine the level which the float willassume. For example, if plug cock 20cwere opened, the liquid would passinto the eduction header 2| through the lowermost circular manifold. Ifplug cocks 20a, 20b, and 200 were closed, the float would assume itsuppermost position and the liquid would be withdrawn through circularmanifold I8. A gas vent 32, controlled by a valve 33 is provided. 'Drainpipe 34 controlledplug cock 20, 20a, 20b, or 20c is opened and theothers closed. The liquids to be mixed are supplied through inlet'-30.The motor 5 is started. The liquids to be mixed will flow downwardly atconstantly increasing velocity due to the fact that the b'ailie II isprovided with a progressively decreasing cross sectional area. Theimpeller I3 discharges the liquid downwardly. The mixture is forced tochange its direction the vanes I5 imparting to it a straight lineturbulent flow. Vanes I6 and I2 prevent a tendency toward whirling. Inthe annular jacket formed by the shell 2 and the bailie II, the" mixturewill flow at a constantly decreasing velocity due to the fact that thecross sectional area of the annular passagewayis constantly increasing.The vanes I3 in the'interior of baflle II also prevent a tendency towardwhirling. The float 22 excludes all air, vapor and/or gas, preventingcavitation and precluding the formation of gas and/or air emulsions. Itis to be noted that, if

A heating or cooling medium may be.

air is present, the resulting oxidizing reaction will accelerate theformation of polymers. The float prevents this oxidation. If air and/orgasoil emulsions are formed, the subsequent separation of the treatingagent is greatly impaired. The intimately contacted mixture is withdrawnthrough its manifold and discharged through header 2| to centrifuges inwhich centrifugal separation of the treating agents is effected.

It will be observed that I have accomplished the objects of myinvention. I have provided a mixing apparatus which permits easyvariation of volumetric capacity. By means of the control which I amable toexercise over the volumetric capacity, I can control the time ofcontact of the material undergoing mixing. I have provided a sealingfioat for the protection of the upper surface of the liquids undergoingmixing precluding the formation of gas and oil, or air and oil emulsionswith the resulting oxidation which would otherwise ensue. The jacketprovides a means for easily controlling the temperature of thecontacting operation. The fiow' homogeneous mixtures.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsub-combinations. This is contemplated by and is within the scope of myclaims. It is'further obvious that various changes may be made indetails within the scope of my claims without departing from the spiritof my invention. It is, therefore, to be understood that my invention isnot to be limited to the specific details shown and described.

Having thus described my invention, what I claim is:

1. In an apparatus for contacting a treating 4 agent with a hydrocarbonoil, a'shell comprising fie and to discharge the same through saidannular passageway, a floating dam within said cylindrical portion, aninlet to said shell for the treating agent and the oil, a plurality ofdrawofi connections communicating with the interior of said shell at aplurality of vertically spaced points and means for controlling saiddrawoffs.

2. In a contacting apparatus, a vertical shell formed with a lowertapered'portion, a liquid inlet to said shell, a tapered baflle withinsaid lower portion spac'edly mounted therefrom to form a passageway ofprogressively varying cross-sectional area, an impeller mounted withinsaid lower portion for circulating liquid within said shell through saidpassageway, a floating dam mounted within said shell, and a plurality ofselective drawoifs from said shell.

3. In a contacting apparatus, a vertical shell formed with a lowerportion enclosing a space of decreasing cross-sectional area, a bafflemounted within said shell in spaced relation thereto and forming apassageway therewith, an impeller mounted within the shell and adaptedto discharge liquid through said passageway and piston means for varyingthe volume of said shell above said impeller.

4. In a contactor, a shell, a liquid inlet means into said shell, aliquid drawoff means communicating with the interior of said shell, anagitating means within said shell, and piston means within said shellabove said agitating means for varying the volumetric capacity of saidshell.

5. In a contactor, a shell, a liquid inlet means, a plurality of liquiddrawolf means, an agitator within said shell, and a piston means withinsaid shell above said agitator adapted to prevent cavitation of theliquid due to the operation of said agitator. v

6. A contactor having a shell, an agitator therewithin, piston meanswithin said shell above said agitator to vary the volumetric capacity ofsaid shell and means for controlling the temperature of the liquid beingcontacted.

7. In a contactor, a shell, 2. liquid inlet means into said shell, aliquid drawoif means communicating with the interior of said shell, anagitating means within said shell, means for controlling the temperatureexisting within said shell, and piston means within said shell abovesaid agitating means for varying the volumetric capacity of said shell.

CHARLES W. S'I'RATFORD.

